Pimozide

Registered South African indications:

• Schizophrenia

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Hypersensitivity to other diphenylbutyl-piperidine derivatives
• Pre-existing congenital prolongation of QT, or family history thereof
• History of cardiac arrhythmias  
• History of Torsades de pointes
• Acquired long QT interval
• Clinically significant cardiac disorders
• Recent acute myocardial infarction
• Uncompensated heart failure
• Arrhythmias treated with class IA and III antiarrhythmics
• Clinically significant bradycardia
• Known uncorrected hypokalaemia or hypomagnesaemia
• Severe central nervous system depression
• Depression
• Parkinson's syndrome
• Coadministration with CYP3A4 inhibiting agents (e.g. azole antimycotics, antiviral protease inhibitors, macrolide antibiotics and nefazodone)
• Coadministration with CYP2D6 inhibiting agents (e.g. quinidine)
• Coadministration with serotonin uptake inhibitors (e.g. sertraline, paroxetine, citalopram and escitalopram)
• Coadministration with QT prolonging agents

Cautions

• Pregnancy
• Breastfeeding
• Renal impairment
• Hepatic impairment
• Elderly
• Cardiovascular disease
• Electrolyte disturbances
• Risk factors for venous thromboembolism
• Abrupt withdrawal
• Long term therapy
• History of seizures or conditions which lower the seizure threshold
• Alcohol withdrawal
• Brain damage
• Conditions which may contribute to an elevation in core body temperature
• Strenuous exercise
• Extreme heat exposure
• Dehydration
• Thyrotoxicosis
• Phaeochromocytoma
• Liver disease

Forms avail. in SA and covered in this monograph: tab

Chronic schizophrenics who respond to the anti-hallucinatory and anti-delusional effects of classical neuroleptics but who do not need the hypnosedative action of such neuroleptics

Chronic antipsychotic maintenance therapy of psychically compensated schizophrenic outpatients

Initial and maintenance therapy in outpatients and in newly or readmitted patients in whom psychomotor agitation, aggressiveness and severe anxiety are not the predominant symptoms

• Oral (tab): Initial: 2-4mg, dly; Titrate by 2-4mg at intervals of 1 week; Maintenance: 2-12mg, dly; Max: 20mg/24hrs

Dosage should be individualised and is best initiated and titrated under close clinical supervision

Dose increases should be made at weekly intervals or longer by increments of 2-4 mg in the daily dose

Not established for use in children below 12 years

Pregnancy

• Caution; not recommended
• The safety of pimozide in pregnancy has not been established. Therefore, it should not be administered to women of child-bearing potential, particularly during the first trimester of pregnancy, unless, in the opinion of the physician, the expected benefits of the drug to the patient outweigh the potential risk to the foetus
• Studies in animals have shown reproductive toxicity but no teratogenic effects have been demonstrated
• Neonates exposed to antipsychotic drugs (including pimozide) during the third trimester of pregnancy are at risk of adverse effects including extrapyramidal and/or withdrawal symptoms that may vary in severity and duration following delivery
• There have been reports of agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress, or feeding disorder. Consequently, newborns should be monitored carefully

Breastfeeding

• Caution; not recommended,
• Pimozide may be excreted in breast milk. If use is considered essential, breast feeding should be discontinued

Renal Impairment

• Caution; no dose adjustment recommended,

Hepatic Impairment

• Caution; no dose adjustment recommended

Elderly

• Caution; dose adjustment recommended
  Elderly patients require half the normal starting dose of pimozide

Porphyria

• Not yet classified (NC)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Dizziness
• Somnolence
• Extrapyramidal disorder
• Akathisia
• Headache
• Tremor
• Lethargy
• Muscle rigidity
• Bradykinesia
• Cogwheel rigidity
• Dyskinesia
• Dystonia
• Dysarthria
• Neuroleptic malignant syndrome
• Grand Mal seizures
• Tardive dyskinesia
• Neck rigidity
• Depression
• Insomnia
• Agitation
• Restlessness
• Extreme exhaustion
• Neonatal drug withdrawal syndrome
• Abnormal electroencephalogram

Cardiovascular Disorders

• Torsade de Pointes
• Ventricular tachycardia
• Ventricular fibrillation
• Prolonged QT interval
• Abnormal ECG

Gastrointestinal Disorders

• Constipation
• Dry mouth
• Vomiting
• Salivary hypersecretion

Genitourinary Disorders

• Nocturia
• Urinary frequency
• Glycosuria
• Erectile Dysfunction
• Amenorrhoea
• Galactorrhoea
• Gynaecomastia
• Decreased libido

Endocrine and Metabolic Disorders

• Hyperglycaemia
• Increased blood prolactin
• Anorexia
• Hyponatraemia
• Hypothermia
• Body temperature dysregulation
• Increased weight

Musculoskeletal Disorders

• Muscle spasms

Skin and Subcutaneous Tissue Disorders

• Hyperhidrosis
• Sebaceous gland overactivity
• Pruritus
• Rash
• Urticaria
• Facial oedema

Sensory Disorders

• Blurred vision
• Oculogyric crisis

Other

• Drug withdrawal syndrome neonatal

• Central nervous system depressants
• Alcohol
• Sedatives
• Hypnotics
• Strong analgesics
• Levodopa
• Anticonvulsants
• QT prolonging agents
• Class IA antiarrythmics
• Disopyramide
• Procainamide
• Class III antiarrhythmics
• Amiodarone
• Sotalol
• Tricyclic antidepressants
• Amitriptyline
• Tetracyclic antidepressants
• Maprotiline
• Antipsychotics
• Phenothiazines
• Sertindole
• Antihistamines
• Terfenadine
• Antimalarials
• Quinine
• Mefloquine
• Anti-emetics
• Metoclopramide
• Sibutramine
• Calcium channel blockers
• Neuroleptics
• Chlorpromazine
• Thioridazine
• CYP3A4 inhibitors
• Azole antimycotics
• Antiviral protease inhibitors
• Macrolide antibiotics
• Nefazodone
• Grapefruit juice
• CYP3A4 substrates
• CYP2D6 inhibitors
• Quinidine
• CYP2D6 substrates
• CYP1A2 inhibitors
• Agents with the potential to cause electrolyte imbalance
• Agents causing hypokalaemia
• Serotonin uptake inhibitors
• Sertraline
• Cisapride
• Bretylium

• ECG 
• Serum electrolytes

Pimozide is a neuroleptic of the diphenylbutylpiperidine series. It is a potent long-acting antipsychotic. Pimozide selectively blocks the central dopaminergic receptors but has minimal effect on the noradrenergic receptors.Pimozide antagonises many of the actions of amphetamine and apomorphine.

Tablet 1mg 

• Orap (LeBasi) originator

Tablet 4mg 

• Orap (LeBasi) originator